The Bill Parcells coaching tree has borne fruit (Bill Belichick) and nuts (Bobby Petrino). Mike Zimmer is hoping the roots are still alive.

Zimmer is the latest of the prominent Parcells’ head coaching disciples. With Teddy Bridgewater healthy, Zimmer emulated Parcells’ program-building plans. With Bridgewater hurt, Zimmer is reprising Parcells’ emergency tactics, which established Parcells as one of the greatest coaches ever.

Parcells and Zimmer both planned to build around first-round quarterbacks from the state of Kentucky. For Parcells, it was Phil Simms of little Morehead State. For Zimmer it was Bridgewater, who revived Louisville.

Neither was drafted to imitate Peyton Manning. Both were trusted to run a physical offense, convert third downs and lead the team.

Yes, there was a time when Simms was not the announcer who annoys a nation, but a great big-game quarterback. When Parcells lost Simms, he did legendary work. Zimmer once again will try to follow his mentor.

Parcells won two Super Bowls — one with Simms, and one without him. If Zimmer can win without Bridgewater, this year’s Vikings team probably will look a little like the 1990 New York Giants.

That season the Giants relied on Simms’ unspectacular efficiency for the first 14 games. He completed only 59 percent of his passes while throwing for 15 touchdowns and four interceptions. In the 14th game, he broke his foot. Parcells turned to his backup, Jeff Hostetler, an athletic but unproven player who had started one NFL game.

The Giants not only won the Super Bowl, they did so by upsetting the two most talented NFL teams of that era — the Joe Montana 49ers and the Jim Kelly Bills.

Parcells relied on 33-year-old running back Ottis Anderson, who after that Super Bowl started only one more NFL game. Anderson averaged a woeful 3.5 yards per rush.

No Giants receiver that season gained more than 541 yards. Stephen Baker and Mark Ingram made Stefon Diggs look like Randy Moss.

Parcells had a backup quarterback who would prove to be a journeyman. He had a statistically terrible running game. He had no star receiver. His key opponents were stocked with Hall of Famers at the skill positions.

He won with defense and by managing situations, and with whatever it is that defines great coaching.

In the postseason, the Giants beat Chicago 31-3 in the divisional round. In the NFC Championship Game, the Giants upset the defending Super Bowl champion 49ers in San Francisco 15-13, while breaking Montana’s finger and giving him a concussion.

In the Super Bowl, Parcells faced the Bills, who had yet to lose a Super Bowl. The Bills beat Oakland 51-3 in the AFC Championship Game. The game was billed as a mismatch.

When it was over, the Giants had won 20-19, and Parcells had achieved a career-defining victory.

I covered Parcells’ upsets of the 49ers and Bills. There was a sense of shock in both stadiums, as if a magician had just sawed someone in half without giving away the trick.

Zimmer faces difficulties. He built his team around Bridgewater. He has yet to win a playoff game, and now hopes to do so while introducing Sam Bradford to his offense. He coaches a franchise that has never won a Super Bowl.

The other day Zimmer said he reached out to Parcells after Bridgewater’s injury.

If Parcells was as blunt as usual, he probably told Zimmer, “Buck up, buddy. In 1990, I would have killed to have players as good as Adrian Peterson, Stefon Diggs and Sam Bradford.”